| A | B |
|---|
| abiotic factor | nonliving thing in an ecosystem |
| biotic factor | living thing in an ecosystem |
| commensalism | one is helped and one is not helped or harmed |
| competition | struggle for food or shelter |
| ecology | study of natural environments |
| ecosystem | all biotic and abiotic factors in an area |
| energy pyramid | how food energy moves in an ecosystem |
| food web | diagram showing what eats what |
| invasive species | organisms that aggressively spread |
| mutualism | both organisms benefit |
